Under which condition may deadly force be used?

The use of deadly force is a serious matter governed by strict legal and ethical guidelines. It is considered appropriate when there is an imminent threat to life. The correct choice emphasizes the principle that deadly force can be justified when an individual is protecting their own life or the life of another person. This reflects the fundamental right to self-defense, which is recognized in legal frameworks to preserve life in situations where there is a clear and immediate danger.

In scenarios involving robbery, theft, or vandalism, while property protection is important, these circumstances do not typically justify the use of deadly force unless there is a direct and serious threat to life. Therefore, the focus of the correct choice is on the preservation of life rather than property, indicating that the response must align with the severity of the threat being faced.